Rotor unit



Dec. 19j, 1944.

A. w'. THOMANN ET Al.

ROTOR UNIT 2 Sheets-Sheet l I Filed March 2, 1944 Dec. 19, 1944.

A. w. THOMANN ETAL ROTOR UNIT 2 Sheets-.Sheet 2 Filed March 2, 1944 ATTORNE V...ciiically pointed out in the claims.

Patented Deo'. 19, 1944 ases-,31e

Ro'ron Arthur:r W'. Thomann, Nutl'e, andi. George F.`

Wslicenus, Summit, L, assignors to Worth.- ington Bump ami Machinery (lorporation', Harrison, Nr l., a corporation of' Delawarev Application March 2 1944', Serial No.K 524,114

(i Claims..

Thisv invention relates tcy centrifugal machines such asl pumps, compressorsv and the, like, and

more particularlyI toa rotor for such machines` in which the impellers are permanently or semipermanently attached to the rotor shaft by pin means which lie in the planes of the respective wearing faces of the impellers, and in which those portions of the pin means exposed through the wearing surfaces may be machined simultaneously with the impellers after complete assembly of the rotor.

Another object is to providel a rotor wherein the impellers of the' respective stages are permanently attached to the rotor shaft, and in which pins are employed for fastening the impellers to the shaft, with the pins so arranged as to provide a durable structure, in addition to unobstructed accessibility for assembling purposes.

A further object is to provide a rotor wherein a series of stage impellers is pinned to the rotor shaft in a permanent manner, and in which the pins are so anchored as to preclude accidental unloosening thereof.

With these and other objects in view, as may appear from the accompanying specification, the invention consists of various features of construction and combination of parts, which Vwill be first described in connection with the accompanying drawings, showing v`v.a rotor.:` unit of -a preferred form embodying the invention, and

the features forming the invention will be spe- In the drawings: f vFigure 1 is a longitudinal sectional view of a centrifugal pump' embodying the present tion.

' Figure 2 is an enlarged longitudinal sectional view of a portion of the rotor.

Figure 3 is asectional view taken along the line 3-3 of Figure 2.

Figure 4 is a sectional detau view of a, portion of one of the impellers.

Figure 5 is a sectional view taken along the inven- (CL 10S-115) a. rotor [0. is mounted in a'casing IiI. This rotorV includes a shaft I2 on which impellers I3. are perma'nently or semi-permanently mounted. Each impeller includes a side wall or disc I4 provided with an annular wearing surface I5, and all the wearing surfaces I5 are of the same diameter. The shaft I2 is undercut at I6, the undercuts comprising circumferential grooves. The Walls I4 are mounted on the cylindrical portions l1 of the shaft I2, and the walls are provided with bores I 8 press fitted to the cylindrical portions.

Annular rings I9 are arranged between the walls I4, which rings are provided with annular wearing surfaces v2|) `of the same diameters as the wearingv surfaces I5. Outward flow fluid vanes 2| xedly connect the rings I9 with their respective walls I4, and the rings are of such sha-pe and arranged in such manner as to co-act with the walls I4 and the faces ofthe undercuts I6 to provide fluid passages 22 generally U- shaped in cross-section. Figure 1 illustrates the inlet eye of the pump at 23, which eye has communication with the suction inlet 24 of the pump. The last stage impeller 25 has communication with the pump discharge 26. Each fluid passage 22 extends circumferentially of the axis of the rotor I0, and the legs 21 and 28 of the iiuid passages comprise fluid inlets and fluid outlets, respectively. Both the fluid inlets and the fluid outlets extend 360 about the rotor and open through the annular perimeter thereof. The vanes 2| are arranged in the legs 28 of the -respective uid passages 22, and the side faces of a series of stage pieces or annular members 3U 34 co-acting with the stage pieces to provide fluid passages 35 having fliid inlets 36 and uid outlets 31 communicating with the uid outlets 28 and fluid inlets-21, respectively. Casing rings 38 and 39 are attached to the flanges 40 and 4I, respectively, of the stage piece 3 0 and diffuser 34. The casing rings 38 and 3 8 having wearing surfaces 42 and 43 arrangedin co-active relationship with the wearing faces 20 and' I5, respective- 1y. A11 the wearing surfaces 42 and 43 are substantially of the same diameter-so that the rotor y opening toward the walls 49.

threaded into the walls 49 and 50 to pre'vent accidental disconnection of the two wall parts. The` I may'be axially removed as a unit from the casing II, since no part of the rotor is of larger diameter than the wearing surfaces I and, 20, and the Wearing surfaces 42 and 43 define t-he smallest inside diameter of the casing II.

A machine of the foregoing type, particularly with respect to axial removability of the rotor intact from the ca "ng, forms the subject matter of an application for patent on centrifugal pump filed by George F. Wislicenus, a joint -inventor herein, on even date herewith. The present nvention is primarily concerned with the attachment ofA the impeller or impellers to the rotor shaft. v

Means for fastening the walls I4 to the shaft I2 comprise pins 44 having a press nt in radial bores 45 in the walls and opening through the wearing surfaces I5. The inner ends of the pins 44 press fitted in bores 46 in the cylindrical portions I1. The bores 45 are of enlarged diameters at their outer ends for the reception of plugs 4 'I threaded into lthe bores, since the outer ends of the pins 44 terminate some distance inwardly from the wearing surfaces I5. The plugs 41 bear against the outer ends of the pins 44 to prevent, loosening of the pins. In building the rotor, all the Walls I4 are attached to the shaft I2 before machining of the rotor. Thus the plugs 41 are machined simultaneously with the walls I4 so that the` exposed ends of the plugs constitute portions of the annular Wearing surfaces I5.

Accordingly, the rotor may be accurately machined in one setting and dynamically balanced as a whole.

In view of the fact that the wearing surfaces end that the rotor may remain perfectly balanced.

Means for xedly securing the casing rings 38 and 39 comprise screws 53 extending through the anges 54 on the casing rings and threaded into the flanges 40 and 4I, respectively.

The shaft I0 extends through stufling boxes 55 and 56 carried by end covers 51 and 58, respectively, the end covers being detachably connected with the end pieces 3| and 32, respectively, by bolts 59. A balancing drum 60 is attached to the shaft I2 at the discharge end of the pump, which drum lies within the plane of a balancing drum head 6I.

Obviously the foregoingstructure is equally well adapted for use in compressors, turbines and the like Without departing from the spirit of the present invention.

It will be understood that the invention is not to be limited to the specific construction or arrangement of parts shown, but that they may be widely modified Within the invention dened by the claims.

What, is claimed is: l. A rotor unit comprising a shaft, impellers mounted on said shaft and having wearing surfaces of diameters atleast equal to the outside t spaced cylindrical portions, impellers having an- I5 denne the largest diameter of the rotor, location of the fastening means for the impellers in the planes of the walls I4 provides unrestricted accessibility which greatly facilitates assembly of the parts. All work vis done from a position beyond the annular perimeter of the rotor. The walls I4 are of such thicknessas to amply accommodate the bores and the plugs 41 so that the impeller fastening is of durable construction.

Since the rotor IIJ may be axially removed intact from the casing, the impelle structure may be permanently attached-to the rotor shaft, in

the manner shown; should removal becomenecessa'ry, the pins 44 are provided with threaded bores 48 into which a suitable pulling tool may be threaded. Before the pins 44 can be withdrawn, however, it' is necessary to either remove the plugs 41 or open the plugsto gain access t0 the threaded bores 48. Y gained by boring openings of sufficient t:size throughA the plugs.

Ihe rings I9 comprise wall portions which are fixed to the vanes 2I. The walls 49 are generally L-shaped in cross-section. Second walls 50 are attached to the walls 49, the walls 50 being in the nature of channels in cross-section and Screws 5I are walls 49 and 50, because of their cross-sectional contours, provide cavities in the rings I9 so-that the latter are of Vhollow formation, thereby requiring less material and reducing the weight of the structure. While the walls 59 are press-fitted to the walls 49, leakage might occur between some Such -access may be nular walls provided with bores press-tted to the respective cylindrical portions, said* annular walls having wearing surfaces of diameters at least equal to the outside diameters of their respective impellers, and pin means' extending radially through said annular walls and into said cylindrical portions to flxedly connect the indi-l vidual impellers with said shaft, said pin means extending through the periphery of the walls of the impellers.

3. A@ rotor comprising impellers having walls provided with openings, a rotor shaft extending through said openings, and means extending radially through said walls and into said shaft for fixedly connecting the impellers with said rotor shaft, said walls being provided with machined wearing surfaces and Vsaid means having faces machined in continuation of said wearing surfaces.

4. A rotor comprising impellers having annular walls provided with openings, a rotor shaft pressiitted4 in said openings, the Vrespective annular Walls and said shaft having co-axial bores, said bores extending radially through said walls and their annular perimeters,.pins insaid bores for flxedly attaching the individual impellers to said shaft but terminating short of the outer ends of said bores, and means secured in the outer ends of said bores and engaging said -pins to restrain the latter from relative outward movement in the bores, said walls having machined wearing surfaces a-nd said means having faces machined in' or said bores, and plugs threaded into the outer ends of said bores and engaging said pins to restrain the pins from relative outward movement in their respective bores, said walls having machined wearing surfaeesand said plugs having faces machinedy in continuation of said wearing surfaces.

6. A rotor comprising impellers having annular r walls provided with openings, alr'otor shaft presstted inv said openings; the respective annular l0 walls and said shaft having co-axial bores,l said bores extending radially through said-'walls and their annular perlmeters. fitted in said bores for ilxedly attaching the individual impellers to vsuriaceasaid pins being provided with threaded openings in their outer ends for connection with a pin withdrawing tool after removal of the respective plugs.

, ARTHUR W. THOMANN.

lCillORG/E l". WIBLICENUS. 

